Radiator assembly with booster control



Oct. 6, 1964 R. w. KRiTZER 3,151,670

mums ASSEMBLY wmq ssos'raa CONTROL Filed July 30, 1962 Fig F 52 w 7 cs lA/V'NTOR R/CHARD l V. KR/TZER ATTORNEY United States Patent 3,151,679 RADIATG-R ASSEMBLY WITH BGOSTER CQNTRGL Richard W. Kritzer, Chicago, 111., assignor to Peerless of America, Incorporated, a corporation of Illinois Filed July 3t), 1962, Ser. No. 213,411 2 Claims. (Cl. 165-122) The present invention relates generally to radiator constructions and has particular reference to a radiator assembly which is designed primarily for cooling an inhabitable enclosure and has associated with it booster control means whereby, when normal thermally-induced air flow past the heat exchange surfaces of the heat exchange unit is insuflicient to bring the temperature of air within the enclosure down to a desired minimum, a booster fan is set into operation and overrides the normal thermallyinduced air flow in such a manner that an appreciably greater cooling eiiect is attained by reason of a greater volume of air being drawn through the easing of the radiator assembly from the suction side of the booster fan, this air having more intimate contact with the heat exchange surfaces of the heat exchange unit due to its greater velocity and consequent more efficient sweeping efiect.

In its broadest aspect, the invention contemplates the provision of a radiator assembly including a heat exchange unit which is of the finned tubing type and has the fins thereof so designed and positioned within the associated casing that they offer a minimum resistance to the flow of air thereacross in any direction in which the air is capable of flowing through the casing of the assembly. The casing opens into the associated inhabitable enclosure in such a manner that, normally, when the fluid cooling medium is passd through the finned tubing of the heat exchange unit, the air within the casing is thermally induced to descend verticdly through the casing and be come discharged under the influence of gravity from the lower regions of the casing, thus pulling replacement air into the casin through the upper regions thereof. It the cooled air thus introduced into the enclosure is suificient to satisfy the cooling demand, the radiator continues to function in this manner indefinitely. However, if the thermally-induced flow of air is insufiicient to satisty the demand for cooling, a booster fan in associated relation and forming a part of the radiator assembly is automatically set into operation, either manually or automatically, and air is drawn from the enclosure into the casing and caused to traverse the heat exchange surfaces (tins) of the heat exchange unit in a direction different from the direction of thermally induced air flow, the new path of air meeting the fins in an edge-to-edge direction throughout a greater edge area, thereby increasing both the heat-exchange efficiency of the radiator assembly as a whole and the volume of air flow so as to bring the temperature of the enclosure rapidly down to the desired minimum.

it is further contemplated that, in order to confine the suction-induced stream of air to the region of heat exchange, a damper be provided to channel or guide the air flowing to the suction side of the booster fan into close proic'mity to the heat exchange surfaces, principally the edge surfaces, and prevent short-circuiting of air from the enclosure directly to the suction side of the booster fan without first encountering an appreciable number of the heat exchange surfaces.

The provision of a radiator assembly of the character briefl outlined above being among the principal objects of the invention, various other objects and advantages, not at this time enumerated, will become more readily apparent as the following description ensues.

In the accompanying single sheet of drawings forming a part of this specification, one illustrative embodiment 3,151,676 l mented Get. 6, 1964 of the invention has been exemplified in the form of an elongated baseboard radiator assembly of small height and appreciable horizontal or longitudinal extent, the principles of the invention being particularly applicable to a structure of this nature. It is to be distinctly understood, however, that the invention is not necessarily limited to a baseboard-type radiator assembly and that, if desired, the principles of the invention may be applied to various types of space heaters, whether the general direction of tubing extent be horizontal or vertical or whether the casing be elongated in one direction or the other. I respective, however, of these specific details, the essential features of the invention are at all times preserved.

in the one sheet of drawings:

FIG. 1 is a sectional view taken substantially centrally vertically and longitudinally through a baseboard radiator assembly constructed according to the principles of the present invention;

H6. 2 is a sectional View taken on the line 22 of FIG. 1; and

FIG. 3 is a circuit diagram of a thermostat control which may be employed in connection with the present invention when automatic operation of the booster fan is desired.

Referring now to the drawing in detail, the invention has been disclosed herein as being in the form of an elongated baseboard radiator assembly of the type which is adapted to extend horizontally along a floor surface at a region near the juncture thereof with an adjacent vertical wall surface. As previously stated, however, the invention is applicable to other types of radiator constructions, as, for example, a floor-to-ceiling radiator or other upright structure disposed wholly within the enclosure to be cooled or disposed exteriorly of such enclosure and communicating therewith through suitable air passages or openings. The radiator assembly comprises a casing 18 which is generally in the form of a trapezium i transverse cross section and includes a bottom wall 12, a vertical back wall 1 a forwardly and upwardly inclined top wall 16, a partial front wall 18, and a pair of wi ely spaced end walls 2% and 22. A transverse partition wall 24 divides the casing 10 into a relatively short fan compartment 25 and a relatively long cooling compartment 28, the compartment 26 being disposed adjacent to the end wall 22.

The compartment 26 in the casing It has mounted therein a booster fan 3% in the form of a conventional motor-driven, centrifugal blower assembly. The com partment 2% has mounted in it an elongated heat exchange unit 32.. The walls 12, lid, 16 and 13 are common to the two compartments 25 and 28, the front wall 18 being provided with a series of louvres 36 in register with the exhaust side of the booster fan 34 The partition wall 24- is provided with an opening 42 in communication with the intake or suction side of the motordriven booster fan 39, this opening being disposed in the lower regions of the partition wall 24. As will be described in greater detail subsequently, when the operation of the present radiator assembly is set forth, when the booster fan 3% is in o eration, the flow of air through the cooling compartment 28 is generally in a longitudinal direction.

The heat exchange unit 32 is essentially of the fin and tube type and may assume various forms. However, in the illustrated form or" the invention, it consists of a length of cylindrical tube stock 56) (hereinafter referred to as tubing) and a series of closely-spaced radiating fins 52 which are secured to, and extend generally radially outwardly of, the tubin The tubing 5% extends longitudinally through the casing 16 and is supported in the end walls 2% and 22 and in the partition wall 24 by means of suitable supporting heads 54-. The tubing 50 is adapted to have a suitable fluid cooling medium, such as chilled water, brine or the like, circulated through it.

The various heat-radiating fins 52 per se form no part of the present invention. Preferably, they are like those which are shown and described in United States Patent No. 2,903,246, granted to me on September 8, 1959, and entitled Baseboard Radiators. The fins 52 are substantially identical and are in the form of sheet metal stampings of copper, brass, aluminum or other metal having high heat-conducting characteristics or properties. Each fin includes a central imperforate hub portion 56 having 'a central opening 58 which is surrounded by a lateral annular flange oil. The tubing 56 passes through the flanges 60 of the fins 50 and is expanded radially outwardly to effect such a union between the tubing and fins as to insure high heat transfer properties between the parts. Relatively long heat-assimilating fingers '62 extend upwardly from the upper regions of the hub portions 56 and relatively short heat-assimilating fingers 64 extend downwardly from the lower regions of the hub portions. The fingers 62 and 64 are twisted at an angle of 90 from the planes of the hub portions 56 so as to provide small spaces between adjacent fingers and thus enhance the flow of air along the tubing Stl in a longitudinal direction and transversely through and past the upper and lower regions of the fins 52 of the heat exchange unit 32.

It is to be noted at this point that whether the air within the casing 16 flows vertically upwardly through the casing or whether it flows longitudinally along the casing, the side edges of the twisted fingers 62 and 64 are disposed well within' the paths of moving air with the result that heat assimilation into these edges is enhanced. It is a matter of common knowledge that, .in connection with any heat radiating or heat assimilating fin, the amount of heat transfer which takes place at these edges is greater than the heat transfer which takes place at comparable areas along the planar faces of the fin.. Thus, the placement of these side edges of the fingers 62 and 64 well within the path of moving air contributes materially to the efiiciency of the present radiator assembly.

Referring now to FIG. 2, means are disclosed therein whereby, when a cooling fluid, such as chilled water, is supplied to the tubing 50, a thermally-induced flow of air will be induced within the cooling compartment 23, this fiow'of air being directed generally downwardly through the compartment. Accordingly, the partial front wall 13 provides an elongated air inlet opening 70 between the upper edge thereof and the forward edge of the top wall 16. Similarly, the partial front wall 18 pro vides an elongated air opening 72 between the lower edge thereof and the forward edge of the bottom wall 12 .These openings 79 and 72 are substantially coextensive with the longitudinal extent of the compartment 28. Due

to Well-known isothermal and adiabatic processes, when the air Within the cooling compartment and in close proximity to the heat-assimilating fins 52 yields up heat to the fins, the air contracts and, consequently, has a tendency to descend under the influence of gravity, thus drawing warmer air inwardly and downwardly through the inlet opening 70 and discharging cooled air outwardly through the opening 72. A reasonably free flow of air downwardly around the various fins 52 is assured by 5 reason of the fact that this air is not appreciably obstructed by the lateral turning or twisting of the various heat-assimilating fingers 62 and 64. i

In the operationof the present radiator assembly, it is contemplated that the aforementioned thermally-induced i flowof chilled air downwardlythrough the casing and outwardly through the elongatedopening 72 will satisfy the most moderate demands for cooling so that the boostfan, which 'is electrically'operated, may remain deenerd greater cooling eflect to produce a lower temperature within the enclosure with which the radiator assembly is associated, the fan 39 will be set into operation in a manner that will now be described in detail.

The fan 39 is driven by an electric motor M, which, as shown in FIG. 3, is operatively connected through leads 13 and 15 to a suitable source of current supply, such as a wall outlet, leading from a 110 volt power line. An

oft-on control switch CS may be disposed in the lead 13 for manual control of the motor M if desired, but if auto matic operation of the motor M is required, a conventional room thermostat T may be disposed in the lead 13 in serie with the switch CS.

Assuming now that automatic operation is desired and also that the enclosure with which the radiator assembly is associated be maintained at an even temperature of F., if the temperature within the enclosure is at or below this rating, the thermostat T will cause the circuit for the motor M to be open so that the fan 3% is inoperative and a thermally-induced flow of air downwardly through the casing 10 will obtain in the manner previously described. If this flow of thermally-induced cooled air is sufiicient to maintain the required temperature, the thermostat will maintain the motor M deener- 'gized, and the flow of air downwardly through the casing and past the various fins'52 will continue indefinitely. However, if the temperature rises above the required temperature of 70 F., the thermostat T will close the electric circuit for the motor M, thus energizing the same and causing the fan 30 to be set into operation. The fan will then draw air through the opening 42 in the partition wall 24 and discharge the air under pressure through the louvers 36 in the front wall 34 of the compartment 26. Where the length of the cooling compartment 28 is not great so that the suction exerted by the fan 39 through the opening 42 in the partition wall 24 will be effective throughout the entire length of the heat exchange unit 32 and will draw air through the spaces existing between the adjacent laterally-turned fingers 62 and 64 of all of the fins 52, the lower opening 72 may be allowed to remain open at all times, so that, when the fan is operated, air will be drawn into the casing through both the lower opening 72 and through the upper opening 70. Most of the air which enters the casing through the upper opening 74 will pass through the spaces existing between adjacent pairs of laterally-turned, heat-assimilating fingers 62, while most of the air which enters the casing through the lower opening 72 will pass through the spaces existing between the adjacent pairs of laterally turned heat-assimilating fingers 64. All of the air passing between these fingers will be drawn through the opening 42 in the partition wall 24 for subsequent discharge through the louvers 36 in the front wall 13. However, if the cooling compartment is relatively long so that the suction exerted at the opening 42 is insuificient to pull air through only th fins 52, which are relatively close thereto, it will be necessary to close the lower opening 72 when the booster effect of the fan 39 is desired. Accordingly, a pivoted damperp of elongated design is mounted within the air discharge ing effect or the booster fan 39 is not needed, and this 77 opening 72, this damper. being adapted to be closed across the opening when the fan 30 is in operation. 7 If desired,

the damper 80 may be manually operated, but to render the radiator assembly fully automatic in its operation, the damper is preferably pivoted to'the upper edge of the discharge opening 72,'as shown in FIG. 2, and is balanced or biased by means of a weight 84 which'is carried at the outer end of'a torque arm 86 having a short pilot vane 88 disposed thereon. In its free state, the damper 80 assumes the substantially horizontal open position in which it is shown in full linesfin'FIG. 2, with the vane S Sbeing disposed'within the opening 72. When the fan'3 0is set 7 'into operation, the consequent reduction of air pressure within the compartment to a subat mospheric value will' .cause a momentary in-rush' of air through the opening 72.

This in-rushiug air will strike the vane 88 and swing the damper 80 toward its closed position across the opening 72. As soon as the damper moves into the air stream entering the opening 72, the air will strike the damper itself and cause the same to be swung to its fully closed position against a fixed limit stop 90 on the bottom wall 12 of the casing. Thereafter, the pressure of atmospheric air on the outside of the damper will serve to maintain it closed as long as the fan 30 is in operation. During such operation of the fan 30 and with the damper 813 closed, air will be drawn into the cooling compartment 28 only through the upper air inlet opening 7%. Closure of the damper 80 enhances the flow of air through the remote regions of the compartment 23 where, ordinarily, and in the absence of the damper, the full capacity of the fan 39 will be taken up by an in-rush of air through the opening 42 from the adjacent regions of the heat exchange unit where less frictional resistance is offered to the air than is ofiered at the remote regions.

The above described booster eifect which obtains as a result of energization of the motor M and consequent operation of the fan 30 Will draw air into the casing through the upper opening 70 and efiect intimate heat exchange relationship between the air and the heat-assimilating fins, the efficiency of the heat exchange being materially greater than is the case when thermal flow of air alone is relied upon due to the sweeping action of the air as it passes through the various fins with increased velocity. Furthermore, due to the relatively long side edges of the various laterally-turned, heat-assimilating fingers 62 and 64, as compared to the shorter end edges thereof, a considerably greater edge area is presented to the direction of air flow when the fan 30 is in operation than is presented when thermal air flow alone is relied upon for heat exchange purposes.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. For example, although the damper 80 has been shown and described herein as being balanced for automatic operation under the influence of air flow thereagainst and of the subatmospheric pressure maintained within the compartment 28 after the damper has become closed, it is contemplated that the damper may be solenoid-actuated under the control of the thermostat T, if desired. Therefore, only insofar as the invention has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

1. A radiator assembly adapted for use in an inhabitable enclosure and comprising a casing providing an elongated horizontally extending cooling chamber having widely spaced end walls, a heat exchange unit of the finned tubing type disposed within said chamber and including a length of tubing substantially coextensive with the length of said chamber and from which there projects radially outwardly therefrom a series of closely spaced heat-assimilating fins, said chamber being provided with an elongated air inlet opening in the upper region thereof substantiflly spanning the distance between the end walls, and a similarly elongated lower air opening in the lower region of the chamber, said lower air opening substantially spanning the distance between said end walls so that when a cooling media is supplied to the length of tubing, air will be constrained to enter the air inlet opening and flow generally downwardly through the chamber into heat exchange relation with the series of fins and then flow through said lower air opening outwardly of the chamber, each of said fins including a generally planar hub portion secured to the tubing and extending radially thereof, and a series of heat-assimilating fingers which are turned out of the plane of the hub and extend in parallelism longitudinally of the tubing, one of said end walls being provided with an opening, a motor-driven blower disposed adjacent to said one end Wall and having its suction side in communication with the chamber through said opening in the one end wall and having its discharge side in communication with the aforementioned enclosure, said blower being adapted, upon energization thereof, to draw air inwardly through said air inlet opening and said lower air opening horizontally along the heat exchange unit and through said opening in the one end Wall and finally to discharge the air back into said enclosure, and means for selectively energizing and deenergizing said blower.

2. A radiator assembly as set forth in claim 1 and including, additionally, a gravitationally balanced damper mounted within said lower air opening and operable in response to sub-atmospheric pressure within said chamber to efiect closure of said lower air opening whereby air is drawn by said blower into the chamber solely through said air inlet opening as a preliminary to being discharged back into the enclosure.

References Cited in the file of this patent UNITED STATES PATENTS 2,503,764 Ott Apr. 11, 1950 2,825,506 Steinen Mar. 4, 1958 2,903,246 Kritzer Sept. 8, 1959 2,903,247 Kritzer Sept. 8, 1959 2,927,780 Seeley Mar. 8, 1960 3,074,477 Whalen Jan. 22, 1963 FOREIGN PATENTS 568,060 Canada Dec. 30, 1958 

1. A RADIATOR ASSEMBLY ADAPTED FOR USE IN AN INHABITABLE ENCLOSURE AND COMPRISING A CASING PROVIDING AN ELONGATED HORIZONTALLY EXTENDING COOLING CHAMBER HAVING WIDELY SPACED END WALLS, A HEAT EXCHANGE UNIT OF THE FINNED TUBING TYPE DISPOSED WITHIN SAID CHAMBER AND INCLUDING A LENGTH OF TUBING SUBSTANTIALLY COEXTENSIVE WITH THE LENGTH OF SAID CHAMBER AND FROM WHICH THERE PROJECTS RADIALLY OUTWARDLY THEREFROM A SERIES OF CLOSELY SPACED HEAT-ASSIMILATING FINS, SAID CHAMBER BEING PROVIDED WITH AN ELONGATED AIR INLET OPENING IN THE UPPER REGION THEREOF SUBSTANTIALLY SPANNING THE DISTANCE BETWEEN THE END WALLS AND A SIMILARLY ELONGATED LOWER AIR OPENING IN THE LOWER REGION OF THE CHAMBER, SAID LOWER AIR OPENING SUBSTANTIALLY SPANNING THE DISTANCE BETWEEN SAID END WALLS SO THAT WHEN A COOLING MEDIA IS SUPPLIED TO THE LENGTH OF TUBING, AIR WILL BE CONSTRAINED TO ENTER THE AIR INLET OPENING AND FLOW GENERALLY DOWNWARDLY THROUGH THE CHAMBER INTO HEAT EXCHANGE RELATION WITH THE SERIES OF FINS AND THEN FLOW THROUGH SAID LOWER AIR OPENING OUTWARDLY OF THE CHAMBER, EACH OF SAID FINS INCLUDING A GENERALLY PLANAR HUB PORTION SECURED TO THE TUBING AND EXTENDING RADIALLY THEREOF, AND A SERIES OF HEAT-ASSIMILATING FINGERS WHICH ARE TURNED OUT OF THE PLANE OF THE HUB AND EXTEND IN PARALLELISM LONGITUDINALLY OF THE TUBING, ONE OF SAID END WALLS BEING PROVIDED WITH AN OPENING, A MOTOR-DRIVEN BLOWER DISPOSED ADJACENT TO SAID ONE END WALL AND HAVING ITS SUCTION SIDE IN COMMUNICATION WITH THE CHAMBER THROUGH SAID OPENING IN THE ONE END WALL AND HAVING ITS DISCHARGE SIDE IN COMMUNICATION WITH THE AFOREMENTIONED ENCLOSURE, SAID BLOWER BEING ADAPTED, UPON ENERGIZATION THEREOF, TO DRAW AIR INWARDLY THROUGH SAID AIR INLET OPENING AND SAID LOWER AIR OPENING HORIZONTALLY ALONG THE HEAT EXCHANGE UNIT AND THROUGH SAID OPENING IN THE ONE END WALL AND FINALLY TO DISCHARGE THE AIR BACK INTO SAID ENCLOSURE, AND MEANS FOR SELECTIVELY ENERGIZING AND DEENERGIZING SAID BLOWER. 